Introduction to XSL
OmniUpdate offers XML/XSL functionality that will enable you to take advantage of these technologies to move your website into the future. These technologies are ideal for separating the content of your website from its architecture, and to combine and repurpose content and data. If you have designed your site to take advantage of CSS, then XML/XSL may be the next step for you. And if you want to repurpose content, either produced by you or which comes from some other source, this is certainly the way to go.
Using XML/XSL, combinations of files can be used in a Lego-like manner to produce various outputs such as HTML for web pages, print-friendly HTML, CSV for spreadsheets, PDF's, etc. In addition you can take advantage of XML/XSL technologies to present ever-changing content to keep your website automatically updated with the very latest. However, an XML/XSL approach does require understanding of the technologies and learning how to use them. While you are getting up to speed, you can continue working with OmniUpdate as you do currently. No content or work you did in the past or are now doing need be affected.
The use of XML/XSL technology takes place at the file level when you supply files in new types of formats. The keystone of OmniUpdate's XML/XSL implementation is via the use of a Publish Control File, PCF. OU Campus supports XSLT 1.0, 2.0 and now 3.0.
OU Campus supports two different types of page templates (HTML based, and XML/XSL based). You can learn about HTML based templates here.
XML/XSL page template set: minimally consists of 4 items (TCF, Image, TMPL, XSL)
TCF file (Template Control File) This is an XML document that contains the form questions to customize a new page (from a TMPL file), along with the info on what TMPL file to use (in the template node of this file). This is the same file type and syntax as used for the HTML based templates above.
Image (image icon) The New Page Thumbnail image is a small picture that represents your new template; it will appear on the "Create New Page" page, where it and all other thumbnails will be listed alphabetically. It can look like anything you want it to, but it must be saved as one of the following file types (.png .jpg .jprg, or .gif). Note: the image must have the same filename as the TCF it represents (e.g. newpage.tcf and newpage.png).
TMPL file (Template file) This is an XML only document with the nodes that will contain the content as well as <!-- %echo var="variable_name" --> tags to catch info from the TCF that will populate a page, it also has the instructions on what XSL stylesheet it needs to partner with to create a final page that will be published. This is the processing instruction that must be at the top of the page. This file is structured nothing like the one for HTML based templates. This file has no HTML in it at all. All of the HTML structure for this template belongs in the XSL file. As with HTML based templates, in advanced XML/XSL templates more than one TMPL file can be used with a TCF file and many pages, files, and folders can be created all at once.
When a user fills out the New Page Wizard, the TCF and TMPL work together to create a PCF file on the staging server.
PCF file (Publish Control File) This is an XML file derived from the TMPL that has been populated with content from the variables that are filled out in the TCF form. Users then edit the PCF file with the WYSIWYG editor to place their content.
PCF files and TMPL files (this XML type) are actually the same file, the difference is the TMPL has the <!--%echo var="variable_name" --> tags. The PCF file is created from (copied from) the TMPL, and gets the values from the TCF and replaces the echo var comments with the values of those variables.
When previewed or published, the PCF has the processing instruction in it to call the XSL file to style it, and via the XSL Transformation engine, convert it in to an HTML doc that can be previewed in OU Campus or is published to the production server.
XSL stylesheets can be defined as XML documents which contain XSLT commands (along with HTML and CSS) and are used to transform the contents of XML documents (our PCF files) into many more friendly human readable forms such as HTML and XHTML.
.PCF files act like any other WYSIWYG editable file in OmniUpdate, but is actually an XML file that's processed by OmniUpdate's built-in XSLT transformation engine when published. It's important to note that the use of PCF files is not an all-or-nothing decision. It's common to use HTML files and PCF files together in the same account. PCF files will be processed by XSLT, while HTML files will be published without processing. This provides for a smooth migration to XML/XSL, and eliminates the need to migrate legacy HTML content if desired. Best of all, your users will not know the difference, since WYSIWYG editing is the same for both file types.
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